Opinions On This 50m Steel Span Bridge Without Supports

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Discussion Overview

The discussion revolves around the structural integrity of a 50m steel span pedestrian bridge that is being assembled on-site. Participants explore concerns regarding its stability, the adequacy of information available for making engineering judgments, and the implications of various external factors on its safety.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Exploratory

Main Points Raised

  • Some participants question whether the information in the provided picture is sufficient to assess the bridge's structural strength.
  • Concerns are raised about the stability of a 50m span bridge constructed from three sections without a center support.
  • One participant notes that the truss design using 8 inch (20cm) I-beams and box-beams appears sturdy, but emphasizes the importance of assembly.
  • Another participant humorously suggests that the bridge's strength could depend on the number of pedestrians attempting to break a record.
  • Some participants express uncertainty about the bridge's safety without more detailed design information, including load capacity and safety factors.
  • One participant concludes that since the bridge is under construction by a qualified engineer, it should be structurally sound, but acknowledges that further speculation is unnecessary.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the bridge's structural integrity, with multiple competing views regarding the adequacy of information and the implications of various design factors.

Contextual Notes

Limitations include the lack of detailed design specifications, assumptions about external conditions (e.g., weather), and the absence of a thorough inspection of the bridge's construction.

Point Conception
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The bridge sections in photo are being welded / bolted ? together on site. Is this going to be structurally
strong enough for a pedestrian bridge ?
750x422_812013_1535965137.jpg
 

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Do you seriously think that nothing but the "information" in that picture is enough to base an engineering judgement on?
 
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I see a squirrel, what a cute squirrel. What is that he's eating? :oldeyes:
 
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It will certainly be safer than crossing a ten-lane racing circuit ... :rolleyes:
 
phinds said:
Do you seriously think that nothing but the "information" in that picture is enough to base an engineering judgement on?
No , but without inspecting it the general question is the stability of a 50m span with 3 sections put together on site and no center support
https://www.thaivisa.com/forum/topic/1056216-new-pedestrian-bridge-engineering/?page=4
 
morrobay said:
No , but without inspecting it the general question is the stability of a 50m span with 3 sections put together on site and no center support
https://www.thaivisa.com/forum/topic/1056216-new-pedestrian-bridge-engineering/?page=4
And the answer is ... not enough information
 
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I have only light knowledge of structural design but that truss made of 8 inch (20cm) I-beams and box-beams looks very sturdy. If there had been a center support, the bridge would only remain until a vehicle crashed the center support; a somewhat likely thing to happen.

I agree the assembly of the three pieces is critical.

(Dimensions were estimated assuming the bus is 10 feet (3m) high.)
 
morrobay said:
Is this going to be structurally strong enough for a pedestrian bridge ?
That depends on how many students try to break the "greatest number of people on a bridge" record.
Where is it? India? Or will it be coated in ice during winter, then hit by a hurricane?
The pedestrians are the least of the problems.
 
Tom.G said:
I have only light knowledge of structural design but that truss made of 8 inch (20cm) I-beams and box-beams...
and you are getting this from the picture, how?
 
  • #10
There are some more pictures linked in that forum in post 5. It looks pretty sturdy, but you really can't tell any detail without knowing a lot more about the design.
 
  • #11
cjl said:
There are some more pictures linked in that forum in post 5. It looks pretty sturdy, but you really can't tell any detail without knowing a lot more about the design.
I assumed those were all just examples of the KIND of structure he's talking about
 
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  • #12
Could be. I was under the impression that was the exact structure in question, but regardless, there's no way to say what the safe load and safety factor is without far more info.
 
  • #13
morrobay said:
Is this going to be structurally
strong enough for a pedestrian bridge ?
Based on the fact that it is a real bridge under construction I conclude that it has been designed by a qualified engineer and the plans reviewed and approved by a qualified code enforcement agency and therefore will be structurally strong enough. Anything beyond that - as others indicate - is pointless speculation. Thread locked.
 

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